Combi Boilers

ailishfagan

Hi, I'm interested in switching my heating system to a combi boiler system. Combi boilers seem to be used all over Europe and I like the idea of constant hot water supply. However trying to get information on combi boilers from plumbers of heating suppliers is proving difficult. They don't seem to be used that much in Dublin. I'm worrying is that because they don't work here with low pressure hard water??? Anybody got any experience with this? It'd be of much use. Thanks

ailishfagan

ailishfagan wrote: »

Hi, I'm interested in switching my heating system to a combi boiler system. Combi boilers seem to be used all over Europe and I like the idea of constant hot water supply. However trying to get information on combi boilers from plumbers of heating suppliers is proving difficult. They don't seem to be used that much in Dublin. I'm worrying is that because they don't work here with low pressure hard water??? Anybody got any experience with this? It'd be of much use. Thanks

Lots of combis fitted in Dublin

Combis require a good mains water supply which is hard to find in Dublin, some installers will fit a break tank to store water then pump it to feed the combi, I'm not a fan of this method as I think if you have low mains then a combi isn't suitable.

If you have any specific questions then ask away.

shane0007

They are also not suitable if there is lime in your mains water.

JohnnieK

Good pressure, good flow rate is very important. Lime would have to be addressed if present.

ailishfagan

Thank you so much for this information. Our water pressure is really not that good but we were thinking of fitting a variable feed pump between the storage tank and boiler to help with this. Also for the lime we were going to install a water softener. These two products alone with prob cost in the region of 2k! Is it worth it? The idea of hot water really appeals to me. I spend a fortune on emersions heating water.

Thanks again for passing on your experience!

antoinolachtnai

According to the bylaws, you cannot fit a combi directly to the mains in Dublin. There are a bunch of reasons for this, good and bad, but those are the rules.

http://www.dublincity.ie/SiteCollectionDocuments/Dublin_City_Council_Waterworks_Regulations.pdf - see section 39 in particular.

The way you are proposing to do it seems fine according to the rules. However, you would want to be sure you have plenty of water storage in the attic. And as you say, it is an expensive project.

Why would you not put in a high quality, fast recovery hot water tank, with its own connection to the boiler? This will also give you plenty of hot water. It would certainly be cheaper than what you are describing. If you have a large house with more than one bathroom, it would give you a lot more hot water at peak times, if that is an issue.

You cannot install a water softener without the permission of the City Council.

http://www.dublincity.ie/SiteCollectionDocuments/Dublin_Council_Water_Bye-laws.pdf

Lots of people seem to ignore these bylaws and it probably works out fine, but these are the rules.

antoinolachtnai

antoinolachtnai wrote: »

Lots of people seem to ignore these bylaws and it probably works out fine, but these are the rules.

rules are only as good as the inforcement, i have a site with over 500 38kw combi's mainly used by the council for housing, the council had a say at the design stage, so it would seem rules are of no concern, unfortunately.

DGOBS

That being the case, should not the city council then be held responsible for all the appliance damage done by the hard water they supply instead!

What GOOD reason is there for not fitting a combi?


And as for this one....

6. A person shall not, for conveying, delivering, receiving or using water supplied by the Corporation, fix, fit, or use or cause or permit to be fixed, fitted or used any pipe fitting or apparatus which shall not be of god quality and shall not be in accordance with such of the requirements hereinafter set forth as shall be applicable to it.

How the hell can I get a omnipotent quality fitting!

antoinolachtnai

A good reason for the consumer for not connecting a combi direct to the mains is that there is no guarantee of either pressure or supply. This means that a really bad thing could happen to your boiler.

Another good reason to avoid it is that the pressure might be inadequate in the upstairs part of the house even though it is fine downstairs. Another reason is that the flow of hot watermay not be enough for a house or apartment where two people bathe at the same time.

A good reason for the council to require cisterns is to reduce the peak load on the water network.

A good reason for the plumber not to install a combi would appear to be as follows. If you are a plumber and your customer has these or any other problems, you will be facing an expensive replacement. You won't be able to contest it because the work and the equipment isn't fit for purpose. Even if the homeowner or architect specified a combi boiler, you will still be the guy on the hook because you've broken the local bylaws, which it is your job to know. I don't know a case of this happening myself but it could easily happen.

All my opinion of course. I don't mean to discourage anybody!

DGOBS

I have loads of customers with combi boilers, all love them. The only downside is in event of a water cut there is no storage of water.

The only real reason you gave there is 'peak usage' all other revolve around correct installation of the appliance, kind of a non argument as the 'installer' will be the one responsible not the customer as the installer is deemed 'competent' not the customer.

Combi boilers are not suitable for every installation, usage, water pressure etc are all factors in the decision for/not for fitting a combi. Assuming your installation fits the criteria it is without a doubt one of the best, cost effective and efficient options on the market.

All my opinion of course.

antoinolachtnai

The problem for the installer (or plumber or whatever they arecalled) is that if there is a problem in the future, if the installation has not been done to code (ie the boiler has a direct connection to mains), the installer carries the full responsibility. An example of a problem might be that the water pressure falls in the area. It should not happen, but it could, and the householder has no comeback with the local authority.

It will work In most circumstances and will suit a lot of requirements for sure.

The OP has not given full details of how big their house is, but it does not sound like a great candidate for a combi to me.

antoinolachtnai

antoinolachtnai wrote: »

The problem for the installer (or plumber or whatever they arecalled) is that if there is a problem in the future, if the installation has not been done to code (ie the boiler has a direct connection to mains), the installer carries the full responsibility. An example of a problem might be that the water pressure falls in the area. It should not happen, but it could, and the householder has no comeback with the local authority.

It will work In most circumstances and will suit a lot of requirements for sure.

The OP has not given full details of how big their house is, but it does not sound like a great candidate for a combi to me.

A installer takes a snap shot in time to decide on what is suitable and what is not, if you go by what you say then no sealed system, water heaters or unvented cylinders would be suitable due to possible future events, the OP wants to use a breaktank to deal with the pressure issues which would sort the connection to the mains issue.

antoinolachtnai

If your water authority is willing to guarantee pressure or is at least required by law to provide a certain pressure, and allows direct connections, that approach is absolutely correct.

What the OP proposes to do looks completely legal and workable. The problem with it is that it is a very expensive solution. It is also pretty noisy because it requires the whole water system to be pressurised with a pump in the attic. It seems to me that it would cost less for a good tank and a circuit from boiler to the hot water tank ( which need not be in an old style hot press). If done right, this will heat pretty fast. It will also be much cheaper than an immersion.

DGOBS

I really don't understand that argument, as combi boilers have flow switches, so it the water pressure is too low they won't fire. It's not like they are going to explode, worst case is they would lockout and require a reset!

heinbloed

The OP wrote:

Our water pressure is really not that good but we were thinking of fitting a variable feed pump between the storage tank and boiler to help with this

Find out why that is.
A frequent reason for meassuring low pressure at the house' mains is bad plumbing.
With the 'metered water' now rolling in there is a minimum pressure demanded, the consumption counters (amateurs say meters ) work only between a certain minimum and maximum pressure.
And this EU legislation will bring up the pressure at the counter. It is up to the competent plumber to install a plumbing system which shows low pressure losses.
A new pipe from the main supply/counter will be then the straight answer.

Also for the lime we were going to install a water softener.

There are combi-boilers which take (nearly)any hardness of water on the DHW side, only the amateurs will deny this.

Settlement of lime in a heated system happens mainly at over 60 or 65 degrees Celsius, the laws of physics....

Note that there are answerers to your question in this thread who have been told via this forum how a combi condensing boiler works only a year ago. And who claim to have seen 2 heatexchangers in their life time with a professional career of 30 years (so they say). Others recommend illegal DHW systems no problem. DGOBS isn't meant.

Employ a professional, the term "plumber" isn't protected. Any dud is allowed to work in this profession and advise.
Get a heating engineer in who will advise independantly for a fee and who will controll the installation finally decided for.

Get the energy demand calculated according to
EN 12831 or some other official standard. Without it you are playing lotto with your decisions. This ticket is expensive. You fell before into the cheap-and-easy trap:

I spend a fortune on emersions heating water.

Solar thermal DHW systems usually work cheaper than direct electric or fossile fueled ones. If chosen and installed correctly.


PS

The physical amateur frequently mixes-up the water mains

pressure

with delivered volume per minute.
Make sure you explain the problem correctly, i.e. with numbers,units.

JohnnieK

Aaahhh Heinbloed,Heinbloed. I was only saying to myself the other night that you have been very quite. Low and behold here you are trolling again.

What combi boiler can you get in the irish market that won't clog up with scale? And no strange German ones now that no one can get over here.

DGOBS

It's calcification that's the issue more than just limescale.

But what a post mate, you outdid yourself and insulted everyone in a whole industry in one foul swoop!

In regards to a 'consumption meter' it wouldn't be the correct terminology surely, as the water may or may not be consumed!

heinbloed

JohnnyK is asking:

What combi boiler can you get in the irish market that won't clog up with scale?

Clogging-up: describe this. Do you mean full blockage or a thin layer of lime on the heat exchanger?

OT

And no strange German ones now that no one can get over here.

Funny, the amateur finds leading technology "strange".....and doesn't know how do import it. There are boxes and pallets, JohhnyK .......

It was a German toy manufacturer who developed the first pressurised flow-through boiler and patented it. Pressurised and safe. Some 150 years ago.
Most Irish people hadn't seen a water pipe at this time.


Outsiders would wonder why no one of the professionals have asked the OP for the certified water hardness when reading this thread. Or the pressure. Or the flow rate.

heinbloed

DGOBS wrote:

But what a post mate, you outdid yourself and insulted everyone in a whole industry in one foul swoop!

There are professionals working in the Irish plumbing industry. What I have criticised is the amateurs who obviously are using this forum to dump wages/prices for a job and haven't a clue. Who do not know what the term "system" stands for.
Who neither have done an acceptable job or were worth public's money (" a grant job ").

When a engineer says to the OP (as posted) he should do only two radiators balancing the deltaT Kelvin individually then this man should be brought to the courts. Not just sack him, demand compensation and ask the judge to ban him from the trade.
There are not only politicians who purchase diplomas from an US chicken farm.

I hardly read a plumbing thread like this, DIYers asking DIYers for advise and get it SO wrong.

Why is no one recommending literature to the OP?

JohnnieK

heinbloed wrote: »

DGOBS wrote:

But what a post mate, you outdid yourself and insulted everyone in a whole industry in one foul swoop!

There are professionals working in the Irish plumbing industry. What I have criticised is the amateurs who obviously are using this forum to dump wages/prices for a job and haven't a clue. Who do not know what the term "system" stands for.
Who neither have done an acceptable job or were worth public's money (" a grant job ").

When a engineer says to the OP (as posted) he should do only two radiators balancing the deltaT Kelvin individually then this man should be brought to the courts. Not just sack him, demand compensation and ask the judge to ban him from the trade.
There are not only politicians who purchase diplomas from an US chicken farm.

I hardly read a plumbing thread like this, DIYers asking DIYers for advise and get it SO wrong.

Why is no one recommending literature to the OP?

I forgot your an expert on these matters. What do you do for a living again?

Normally i ignore what you post because the nature of your posts show to us "amatures" that indeed you don't know what your talking about.

And you called me an amature, you haven't a clue regarding my qualifications and im highly offended by that statement yet no infringment is given toward you.

In a nut shell your full of ****.

Now im probably going to get called up on that.

You have done it again wrecked a perfectly good thread.

heinbloed

JohnnyK: please answer the Op's question.

And you called me an amature

I didn't. A(r)matures are - where I come from - taps and valves.

Billy Bunting

Any dud is allowed to work in this profession and advise.

And twats like you get to bad mouth them, why dont you crawl back under the stone you just appeared from.

DGOBS

Your on a roll, no only did you insult an entire industry, now you took a pop at the whole country (your 150 year old joke!)

I would think given your origins one should refrain from throwing insults about our past. As they say about people in glass houses!

KoolKid

Another Infraction for Heinbloed . If you can't learn to be civil & discuss things in a reasonable manner these are going to quickly escalate into a ban.
You have been told enough times. This forum is about people who know helping people who don't . Every thread does not have to be dissected technically.
People give their time here to help each other. They don't deserve to be slagged off , especially by someone who won't even state their qualifications or profession.

heinbloed

heinbloed wrote: »

. Some 150 years ago.
Most Irish people hadn't seen a water pipe at this time.

There's a lot Irish people didn't have 150 years ago;)

DGOBS

Hard to compare ourselves to the self professed superior race!

OP to clarify:):

Combi's Positives: Compact unit requiring no external tanks(unless you use a breaktank) - good for space saving. Perform well with showers. Endless amounts of hot water on demand albeit slowly.

Negatives: Require good mains supply, typically lower flow rates than other systems. Baths can take a long time to fill. Will not support simultaneous demand from several outlets. You cannot install a shower pump to increase performance if you discover your are less than happy.

Economy: You only heat what you need. No storage equates to no standing losses.


Stored hot water Positives: Suitable for addition of booster and power shower pump to provide exceptional flow rates. 

Negatives: Require loft tanks and a hot water cylinder, so provision must be made for the space these will require. An unpumped system will offer low pressure at taps and outlets. 

Economy: Water must be heated and stored whether or not it's used. Important to make sure your system and storage is insulated well to minimise standing heat losses.

heinbloed

Snip

We are no longer going to tolerate these OT rambling and trolling.
Any trolling , off topic or uncivil posts of yours will now be edited or deleted.

If your not going to be civil then we can make it a ban.
I have better things to be doing here so a ban would be easier.
You decide.

DGOBS

That's one big chip on that shoulder eh! You go guy!

As for importing appliances that are nationally unsupported (as in not stocked here by suppliers, of which I am not one nor wish to be one), is a foolhardy exercise as you would find out if you were installing and maintaining them when an issue occurred during a cold spell that required a component.
'sorry love, not heat for week, I have to source and order your part from Germany' in reality, I would just loose custom. If you worked within the industry in this regard you wouldn't wear your rose coloured glasses so much.

heinbloed

DGOBS wrote:

If you worked within the industry in this regard you wouldn't wear your rose coloured glasses so much.

Well, DGOBS, I have imported most of my CH system incl. boiler from China. No problem.
My non-rose tinted lenses are from there as well, can be re-ordered and delivered within 24 hours to the door step. To the door step in Ireland.

Talk to your haulier or the globally experienced manufacturer.

DGOBS

Once again, that's fine as you OWN the system. I takes 3 working days to get parts to my door from the UK your 24hr is dreamland, customers are looking for reasonable cost along with everything else, no gas boiler part suppliers in the UK offer anything but 2-3day part delivery. (besides the air miles etc, there is costs involved in overnight from China!!!)

When dealing with multiple breakdowns PER DAY trying to organize dealing with manufacturers abroad wouldn't be feasible from a logistics point of view (we are mostly sole traders that don't have all day to sit on the phone/internet), most customers would much prefer having an appliance that parts can be sourced locally (preferably the same day) or even in my van stock.

If you were engaged in ongoing work in the industry in this manner, you would see that this wouldn't be acceptable to customers (hence your rose tinted glasses)

To define the Irish as having a superiority complex at least has put a smile on my face, be given you response, the phrase 'one seems to protest too much' springs to mind!

DoneDL

Hamlet, "The lady doth protest too much, methinks."

MiniGolf

DGOBS wrote: »

I have loads of customers with combi boilers, all love them. The only downside is in event of a water cut there is no storage of water.

The only real reason you gave there is 'peak usage' all other revolve around correct installation of the appliance, kind of a non argument as the 'installer' will be the one responsible not the customer as the installer is deemed 'competent' not the customer.

Combi boilers are not suitable for every installation, usage, water pressure etc are all factors in the decision for/not for fitting a combi. Assuming your installation fits the criteria it is without a doubt one of the best, cost effective and efficient options on the market.

All my opinion of course.

Agree totally!

I am currently installing my third Worcester-Bosch combi in the last 5 weeks! Customers love them! (The 7 year warranty helps too )
I am using a submersible pump in the storage tank to supply the combi's in order to ensure a reliable supply and to conform with water regs :rolleyes:
Water flow is no problem as I am getting the full spec of 12 litres per minute.
A boiler will only give good performance if installed to the manufacturers specs.

JohnnieK

MiniGolf wrote: »

Agree totally!

I am currently installing my third Worcester-Bosch combi in the last 5 weeks! Customers love them! (The 7 year warranty helps too )
I am using a submersible pump in the storage tank to supply the combi's in order to ensure a reliable supply and to conform with water regs :rolleyes:
Water flow is no problem as I am getting the full spec of 12 litres per minute.
A boiler will only give good performance if installed to the manufacturers specs.

What model are they giving the 7 year warranty on MiniGolf?

JohnnieK

JohnnieK wrote: »

What model are they giving the 7 year warranty on MiniGolf?

http://kde-electrical.co.uk/wp-content/uploads/Worcester-Bosch-7-year-Promotion.pdf

shane0007

gary71 wrote: »

JohnnieK wrote: »

What model are they giving the 7 year warranty on MiniGolf?

http://kde-electrical.co.uk/wp-content/uploads/Worcester-Bosch-7-year-Promotion.pdf

Is that offer still available? According to that it expired at the end of March.

shane0007

shane0007 wrote: »

Is that offer still available? According to that it expired at the end of March.

I know nuffing, I just used google which our Vissmann t-shirt wearing colleague is to lazy to do:D

MiniGolf

JohnnieK wrote: »

What model are they giving the 7 year warranty on MiniGolf?

From WAI website:
Great news! We have now extended our guarantee promotion until the end of the year. All Greenstar gas-fired CDi and Si boilers and all Greenstar oil-fired boilers will now receive a 7 year guarantee. Plus, from the 1st July 2012 all Greenstar Ri boilers will also qualify for a 7 year guarantee.


MG

JohnnieK

gary71 wrote: »

I know nuffing, I just used google which our Vissmann t-shirt wearing colleague is to lazy to do:D

Sorry Gary, i was ironing my T-shirt at the time :D

Verte11

ailishfagan wrote: »

Hi, I'm interested in switching my heating system to a combi boiler system. Combi boilers seem to be used all over Europe and I like the idea of constant hot water supply. However trying to get information on combi boilers from plumbers of heating suppliers is proving difficult. They don't seem to be used that much in Dublin. I'm worrying is that because they don't work here with low pressure hard water??? Anybody got any experience with this? It'd be of much use. Thanks

Hi Ailish,
Have you had any luck in finding someone to fit a combi? If you have I'd really appreciate any info. Want to get one fitted this summer.

shane0007

Verte11 wrote: »

Hi Ailish,
Have you had any luck in finding someone to fit a combi? If you have I'd really appreciate any info. Want to get one fitted this summer.

Where are you?

Verte11

I'm in D7